Cycle Time Calculator

Calculate total injection molding cycle time from fill, pack/hold, cooling, and mold open/close phases.

Inputs

Fill Time

sec

Pack / Hold Time

sec

Cooling Time

sec

Mold Open / Close Time

sec

Ejection Time

sec

Robot / Delay Time

sec

Tab to move between fields

Results

Total Cycle Time

27.5 sec

Cycles per Hour130.9

Cycles per 8-hr Shift1,047

Cooling % of Cycle54.5%

Dry Cycle Time6 sec

Machine Utilization78.2%

How to Use This Calculator

Enter fill time (sec), pack/hold time (sec), and cooling time (sec) from your process data.
Set mold open/close time, ejection time, and any robot handling delay.
Review total cycle time (sec), cycles per hour, and cycles per 8-hour shift.
Check the cooling-time percentage — if above 60%, focus optimization on cooling circuit design.
Use cycles-per-shift to calculate daily production volume for capacity planning.

How the result changes with Cooling Time

Cooling Time	Total Cycle Time
31	43.5 sec
106	118.5 sec
195	207.5 sec
270	282.5 sec

What each input means

Fill Time: Time for the screw to inject plastic into the cavity.
Pack / Hold Time: Time under packing pressure to compensate for shrinkage.
Cooling Time: Time for the part to solidify enough for ejection.
Mold Open / Close Time: Time for the clamp to open and close.
Ejection Time: Time for ejector pins to push part and retract.
Robot / Delay Time: Additional time for robot part removal, inserts, or other delays.

How this is calculated

Worked example, using the default values

Identify Input Parameters
4 parameters
Fill Time = 1.5, Pack / Hold Time = 5, Cooling Time = 15, Mold Open / Close Time = 3 = 6 input(s) provided
Calculate Total Cycle Time
Total Cycle Time
27.5 = 27.5
Calculate Cycles per Hour
Cycles per Hour
130.9 = 130.9
Calculate Cycles per 8-hr Shift
Cycles per 8-hr Shift
1047 = 1047

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